Context.—: This article is based on a talk given by the lead author at the Eigth Annual Princeton Integrated Pathology Symposium: Breast Pathology, on Sunday, April 11, 2021.
Objective.—: To show how the World Health Organization (WHO) Classification of Tumours links to the requirements for quality assurance in breast pathology, including both immunohistochemistry and molecular pathology.
Data sources.—: The WHO Classification of Tumours 5th edition Breast Tumours entries formed the basis of the talk, together with guidance published by the International Quality Network for Pathology.
Conclusions.—: The WHO Classification of Tumours provides a definitive set of international standards for tumor diagnosis contributed by experts, based on available clinical and research evidence. Techniques used in pathology need internal and external quality assurance to ensure accurate reports for patient management.
© 2022 College of American Pathologists.